It can be appreciated that electrical cores may need to be sealed to a barrier, such as a bulkhead, in order to isolate one side of the barrier from the other. For example the barrier may comprise an enclosure having a noxious or explosive atmosphere on the inside, or there may be equipment within an enclosure which must be hermetically sealed for safe operation.
Various kinds of barrier connector have been proposed. Typically barrier connectors are provided with varying bore sizes, and an operator selects a connector having a bore adequate for the number of cores to be passed through the barrier. Single or multiple cables may pass through a barrier connector, and typically the connector will be specified in relation to the maximum diameter of multiple cores, the maximum diameter of a single core, and the maximum number of cores.
Some means must be provided for sealing the passage through the connector, because no matter how tightly fitted, some interstices between the cores will remain. Frequently these interstices may be quite large, especially if the cores are loosely fitted in the connector.
Usually a two-part epoxy putty is stuffed into the bore of the connector to make a seal—such putty is mixed just prior to stuffing, and cures to a hard substance after about 4 hours. The putty is typically confined within a tight-fitting sleeve within the connector, so as to permit the sleeve and core assembly to be disassembled from the other parts of the connector.
Other features of a typical connector are an ability for attachment to the barrier, and the ability to accept a cable sheath (conduit) which protects the core(s) between the barrier and the equipment to which they are connected in use.
Current designs of barrier connector have disadvantages which the present invention seeks to address.